The pedaling technique thread

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Sep 23, 2010
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coapman said:
Give a breakdown of that 40% at each of these sectors TDC downstroke BDC and upstroke. What is being trained by PC use at TDC and for downstroke
It is not possible to give a breakdown of the different sectors because it will depend upon the starting technique of each individual and how they change. And, of course, those already having good technique (such as demonstrated by Cheung's left leg) wouldn't be able to achieve such a large improvement. That having been said there would be an "average" improvement looking at large numbers of individuals and current "typical" pedaling technique seen in most and if I were to do that I would anticipate that there would be, on average, 3% improvement seen on the downstroke (between 45º and 135º), 12% improvement seen on the backstroke (between 135º and 225º), 10% on the upstroke (between 225º and 315º - what happens if you just get rid of the negative forces), and 15% seen at the top (between 315º and 45º) adding up to 40% improvement overall. If we were to look at someone currently at and FTP of 250 watts 40% improvement gets them to 350 watts, a 100 watt improvement. 7.5 watts would come on the downstroke, 30 watts on the backstroke, 25 watts on the upstroke, and 37.5 watts over the top. Note, the biggest improvements come from improving the weaknesses, not trying to improve what is already strong.
 
Mar 10, 2009
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FrankDay said:
It is not possible to give a breakdown of the different sectors because it will depend upon the starting technique of each individual and how they change. And, of course, those already having good technique (such as demonstrated by Cheung's left leg) wouldn't be able to achieve such a large improvement. That having been said there would be an "average" improvement looking at large numbers of individuals and current "typical" pedaling technique seen in most and if I were to do that I would anticipate that there would be, on average, 3% improvement seen on the downstroke (between 45º and 135º), 12% improvement seen on the backstroke (between 135º and 225º), 10% on the upstroke (between 225º and 315º - what happens if you just get rid of the negative forces), and 15% seen at the top (between 315º and 45º) adding up to 40% improvement overall. If we were to look at someone currently at and FTP of 250 watts 40% improvement gets them to 350 watts, a 100 watt improvement. 7.5 watts would come on the downstroke, 30 watts on the backstroke, 25 watts on the upstroke, and 37.5 watts over the top. Note, the biggest improvements come from improving the weaknesses, not trying to improve what is already strong.


I don't see Cheung applying torque during the upstroke. As TomA on Slowtwitch said, the upstroke is only a means of getting the foot back in position to start another down stroke. The most you can hope for there is to keep it free of negative torque. You say most increase occurs at TDC, what do PC's train here over the 9 months of exclusive use.
 
Sep 23, 2010
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coapman said:
I don't see Cheung applying torque during the upstroke. As TomA on Slowtwitch said, the upstroke is only a means of getting the foot back in position to start another down stroke. The most you can hope for there is to keep it free of negative torque. You say most increase occurs at TDC, what do PC's train here over the 9 months of exclusive use.
Cheung doesn't apply much torque on the upstroke (he does apply some because the upstroke starts at 315º and he is still positive there). But, he isn't applying any negative torque. Getting rid of negatives is the same as applying more positive torque and will result improved power. TomA on ST doesn't know what he is talking about because the upstroke is increasing the potential energy in the leg which is returned on the downstroke because of gravity. He is just trying to rationalize why he doesn't want to work on that. The energy to lift the leg has to come from somewhere. It is more powerful if this come from active use of the muscles of that leg than passively by diverting energy from the pushing leg. What happens on the backstroke matters, it just isn't obvious to many.
 
Mar 10, 2009
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FrankDay said:
Cheung doesn't apply much torque on the upstroke (he does apply some because the upstroke starts at 315º and he is still positive there). But, he isn't applying any negative torque. Getting rid of negatives is the same as applying more positive torque and will result improved power. TomA on ST doesn't know what he is talking about because the upstroke is increasing the potential energy in the leg which is returned on the downstroke because of gravity. He is just trying to rationalize why he doesn't want to work on that. The energy to lift the leg has to come from somewhere. It is more powerful if this come from active use of the muscles of that leg than passively by diverting energy from the pushing leg. What happens on the backstroke matters, it just isn't obvious to many.


All you are referring there is the unweighting technique, muscles do not have to be trained before they are able to do this, they only have to learn how to do it by using one legged pedaling. That should not be included in the extra power PC's have to offer. You still have not explained what PC's are training across the top. Don't forget you also have to exclude inertia across the top and bottom when calculating PC power increase.
 
Sep 23, 2010
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coapman said:
All you are referring there is the unweighting technique, muscles do not have to be trained before they are able to do this, they only have to learn how to do it by using one legged pedaling. That should not be included in the extra power PC's have to offer. You still have not explained what PC's are training across the top. Don't forget you also have to exclude inertia across the top and bottom when calculating PC power increase.
What do PC's train across the top? They train the ability to apply increased forward forces across the top while better following the tangential direction of the pedal forces. While Cheung (left leg) is doing much more across the top than most people do now it is the one area in which I think he could greatly improve. He should be able to get the forces across the top to be the approximate equal of those across the bottom because these forces come mainly from the quads and the hamstrings - two similar muscles in size and strength.

Anyhow, if someone wants to try to train all this stuff on their own I say more power to them. Is it possible to learn how to pedal this way without PowerCranks? Of course it is. Is it easy to do so? No. Greg Lemond once told me (after he first rode the PowerCranks) that he spent years trying to learn how to pedal this way and now people can learn it in months.
 
Mar 10, 2009
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FrankDay said:
Now that has been said, I am really really interested in knowing how it is the thigh is going down at TDC when using your style and not when using other styles.

If we take that reverse Z shape of foot, lower leg and thigh, all muscles here are in almost relaxed mode going over the top when using the mashing style and this puts the top of the thigh in a slightly higher position. With circular or PC pedaling it's worse because the foot is being lifted over the top. Using my semi circular style all muscles in this reverse Z are instantly turned into a maximal forward force producing engine and the tensing of these muscles applying that forward force results in a lower top thigh surface at TDC.
 
Sep 23, 2010
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coapman said:
If we take that reverse Z shape of foot, lower leg and thigh, all muscles here are in almost relaxed mode going over the top when using the mashing style and this puts the top of the thigh in a slightly higher position. With circular or PC pedaling it's worse because the foot is being lifted over the top. Using my semi circular style all muscles in this reverse Z are instantly turned into a maximal forward force producing engine and the tensing of these muscles applying that forward force results in a lower top thigh surface at TDC.
Ugh, you said the thigh was moving down at TDC. It isn't. How high the thigh is is determined by crank length and ankle position. Neither one has anything directly to do with pedaling technique.
 
Mar 10, 2009
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FrankDay said:
He should be able to get the forces across the top to be the approximate equal of those across the bottom because these forces come mainly from the quads and the hamstrings - two similar muscles in size and strength.
Not according to that EMG test, only the knee joint is working there.
 
Mar 10, 2009
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FrankDay said:
Ugh, you said the thigh was moving down at TDC. It isn't. How high the thigh is is determined by crank length and ankle position. Neither one has anything directly to do with pedaling technique.
Ankle position has nothing to do with pedalling technique ? You have not used my TT technique. You asked me to explain and I have done that, I'm still waiting for your 40% power increase explanation.
 
Sep 23, 2010
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coapman said:
You asked me to explain and I have done that, I'm still waiting for your 40% power increase explanation.
??? Check out posts 493 and 495. The only thing I left out was answering the question as to how one increases the forces across the top and bottom. This is a simple matter of starting the contraction of the quadriceps between 10 and 11 o'clock and starting the contraction of the hamstrings between 4 and 5 o'clock, somewhat earlier than what most people do now and stopping those contractions before they become ineffective, around 180º later. Training on independent cranks causes those coordination changes to occur without needing to think about it. In researching this I found this relatively new study from Hug, Bournier, and Dorel entitled Altered muscle coordination when pedaling with independent cranks

from this study:
instructing the participants to actively pull-up on the pedal is unlikely to reproduce the effects induced by the use of independent cranks.
In other words, training with independent cranks is not the same as thinking about pedaling with independent cranks.

As revealed by the large 95% confidence intervals on Figures ​Figures3,3, ​,4,4, there was a high inter-individual variability in the way the participants adapted to these new mechanical constraints. This is particularly clear for TA, RF, and TF. For instance, 3 out of 10 participants did not exhibit any change in RF activity while the others exhibited an increase in activity ranging from +40 to +500%.
In other words, change may depend on what you were doing before and what strategy the rider uses to adapt to the new conditions. Or, peoples results might vary.
 
coapman said:
...
Using my semi circular style all muscles in this reverse Z are instantly turned into a maximal forward force producing engine and the tensing of these muscles applying that forward force results in a lower top thigh surface at TDC.
------------------------------------------
I still do not understand the body position and movements of your 'semi circular' style.

For me (and probably others) to understand and evaluate that style, I need a comprehensive, all in 1 place, description of the bike adjustments such as

seat height (can the pedal be reached with the heel of the foot thru the full pedal circle without hip movement), and with heel on pedal - where is the leg most extended (clock position).

saddle setback (knee position when pedal at 3 o'clock),

handlebar height and reach.

Also needed is description of the rider's technique regarding hip movement (up/down/forward/back), foot and ankle movement and position around the pedal circle, And also what arm movement and force is used in relation with pedaling.

Jay Kosta
Endwell NY USA
 
Sep 23, 2010
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Here is an interesting study (or two).

The effect of prolonged cycling on pedal forces
Contrary to our initial assumptions, it would appear that riders became less effective during the recovery phase, which increased the demand for forces during the propulsive phase. Training the pattern of force application to improve effectiveness may be a useful strategy to prolong an endurance ride.
As I have always said, it is more important to train the last hour than the first. It is why I emphasize that if one is going to train on PowerCranks one also needs to be able to do the long rides and hammerfest rides on them also or they will lose the benefits of what they are trying to do towards the end of the race.

And, a related study: Changes of pedaling technique and muscle coordination during an exhaustive exercise.
The large increases in activity for gluteus maximus and biceps femoris, which are in accordance with the increase in force production during the propulsive phase, could be considered as instinctive coordination strategies that compensate for potential fatigue and loss of force of the knee extensors (i.e., vastus lateralis and vastus medialis) by a higher moment of the hip extensors.
 
Mar 10, 2009
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FrankDay said:
??? Check out posts 493 and 495. The only thing I left out was answering the question as to how one increases the forces across the top and bottom. This is a simple matter of starting the contraction of the quadriceps between 10 and 11 o'clock and starting the contraction of the hamstrings between 4 and 5 o'clock, somewhat earlier than what most people do now and stopping those contractions before they become ineffective, around 180º later. Training on independent cranks causes those coordination changes to occur without needing to think about it. In researching this I found this relatively new study from Hug, Bournier, and Dorel entitled Altered muscle coordination when pedaling with independent cranks

from this study:
In other words, training with independent cranks is not the same as thinking about pedaling with independent cranks.

In other words, change may depend on what you were doing before and what strategy the rider uses to adapt to the new conditions. Or, peoples results might vary.
Why does all PC research end with the words, " Further studies are needed to determine whether these changes are beneficial for cycling performance "
 
Mar 10, 2009
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JayKosta said:
------------------------------------------
I still do not understand the body position and movements of your 'semi circular' style.

For me (and probably others) to understand and evaluate that style, I need a comprehensive, all in 1 place, description of the bike adjustments such as

seat height (can the pedal be reached with the heel of the foot thru the full pedal circle without hip movement), and with heel on pedal - where is the leg most extended (clock position).

saddle setback (knee position when pedal at 3 o'clock),

handlebar height and reach.

Also needed is description of the rider's technique regarding hip movement (up/down/forward/back), foot and ankle movement and position around the pedal circle, And also what arm movement and force is used in relation with pedaling.
The objective of this TT technique is to pedal in such a way that maximal use can be made of the arms to increase power output. Saddle height is got the recommended way with leg fully extended and heel of level shoe on the pedal at 6 o'c but because you slide well back on the saddle the heel cannot reach the pedal at 5 o'c, you are using a toes down position there where the leg is most extended. Saddle set back is not important because you slide back over it and are in almost a similar position to that of a rider who throws his bike at the line. Scott rake clip on bars are needed and handlebars are only slightly lower than saddle. During the pedalling arms are fully extended and as one arm supplies the resistance for that maximal force over TDC the other controls stability and supports all upper bodyweight, changing alternately with the legs. After that it gets too complicated to describe, the best I can do is to say all power generation and application to the pedal is identical to "indoor tug o'war muscle action from ankle to hips in rapid fire mode. You do not start this technique until you have reached a cadence of 60+. You probably still do not understand. Research would not be needed to discover if it was beneficial to performance, as soon as you use it, it would be obvious.
 
Apr 21, 2009
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coapman said:
The objective of this TT technique is to pedal in such a way that maximal use can be made of the arms to increase power output. Saddle height is got the recommended way with leg fully extended and heel of level shoe on the pedal at 6 o'c but because you slide well back on the saddle the heel cannot reach the pedal at 5 o'c, you are using a toes down position there where the leg is most extended. Saddle set back is not important because you slide back over it and are in almost a similar position to that of a rider who throws his bike at the line. Scott rake clip on bars are needed and handlebars are only slightly lower than saddle. During the pedalling arms are fully extended and as one arm supplies the resistance for that maximal force over TDC the other controls stability and supports all upper bodyweight, changing alternately with the legs. After that it gets too complicated to describe, the best I can do is to say all power generation and application to the pedal is identical to "indoor tug o'war muscle action from ankle to hips in rapid fire mode. You do not start this technique until you have reached a cadence of 60+. You probably still do not understand. Research would not be needed to discover if it was beneficial to performance, as soon as you use it, it would be obvious.
If it was immediately obvious you could measure the difference with any power meter.
 
coapman said:
The objective of this TT technique is to pedal in such a way that maximal use can be made of the arms to increase power output.
...
-----------------------
coapman,

thanks for describing the technique - perhaps someone will try to use it in a valid testing situation.

Jay Kosta
Endwell NY USA
 
coapman said:
The objective of this TT technique is to pedal in such a way that maximal use can be made of the arms to increase power output. Saddle height is got the recommended way with leg fully extended and heel of level shoe on the pedal at 6 o'c but because you slide well back on the saddle the heel cannot reach the pedal at 5 o'c, you are using a toes down position there where the leg is most extended. Saddle set back is not important because you slide back over it and are in almost a similar position to that of a rider who throws his bike at the line. Scott rake clip on bars are needed and handlebars are only slightly lower than saddle. During the pedalling arms are fully extended and as one arm supplies the resistance for that maximal force over TDC the other controls stability and supports all upper bodyweight, changing alternately with the legs. After that it gets too complicated to describe, the best I can do is to say all power generation and application to the pedal is identical to "indoor tug o'war muscle action from ankle to hips in rapid fire mode. You do not start this technique until you have reached a cadence of 60+. You probably still do not understand. Research would not be needed to discover if it was beneficial to performance, as soon as you use it, it would be obvious.
Could you post a video of someone using this technique
 
Jan 20, 2010
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coapman said:
The objective of this TT technique is to pedal in such a way that maximal use can be made of the arms to increase power output. Saddle height is got the recommended way with leg fully extended and heel of level shoe on the pedal at 6 o'c but because you slide well back on the saddle the heel cannot reach the pedal at 5 o'c, you are using a toes down position there where the leg is most extended. Saddle set back is not important because you slide back over it and are in almost a similar position to that of a rider who throws his bike at the line. Scott rake clip on bars are needed and handlebars are only slightly lower than saddle. During the pedalling arms are fully extended and as one arm supplies the resistance for that maximal force over TDC the other controls stability and supports all upper bodyweight, changing alternately with the legs. After that it gets too complicated to describe, the best I can do is to say all power generation and application to the pedal is identical to "indoor tug o'war muscle action from ankle to hips in rapid fire mode. You do not start this technique until you have reached a cadence of 60+. You probably still do not understand. Research would not be needed to discover if it was beneficial to performance, as soon as you use it, it would be obvious.
I can visualise the position but wonder about the bolded bits. You realise Scott Rake clip on bars are illegal in competition? It makes the argument for this position redundant.

On the second point a power meter would measure the effectiveness.
 
Mar 10, 2009
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Night Rider said:
I can visualise the position but wonder about the bolded bits. You realise Scott Rake clip on bars are illegal in competition? It makes the argument for this position redundant.

On the second point a power meter would measure the effectiveness.

I don't care what legal or illegal, I had an objective and found the answer which in turn led to the perfect pedalling technique in which the same maximal torque can be applied at 12 as that at 3 o'c and because there is no dead spot sector, you can gain up to an extra 15 mins of effective power application time per hour's pedalling. TT riding position is safer than the 'rest on aero bar' position and the root cause of cycling's lower back pain is eliminated. Why are clip on scott rake bars illegal in time trials, what makes today's aero bars safer.
 
Apr 21, 2009
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coapman said:
I don't care what legal or illegal, I had an objective and found the answer which in turn led to the perfect pedalling technique in which the same maximal torque can be applied at 12 as that at 3 o'c and because there is no dead spot sector, you can gain up to an extra 15 mins of effective power application time per hour's pedalling. TT riding position is safer than the 'rest on aero bar' position and the root cause of cycling's lower back pain is eliminated. Why are clip on scott rake bars illegal in time trials, what makes today's aero bars safer.
Illegal and out of production for 20 years. If your pedalling technique theory was correct it could be easily tested with any power meter.
 
Sep 23, 2010
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coapman said:
Why does all PC research end with the words, " Further studies are needed to determine whether these changes are beneficial for cycling performance "
Ugh, because that is how science is, one study is never adequate to prove anything. In the instance of this study, the authors showed that independent cranks significantly change the pedaling coordination of cyclists who currently use fixed cranks. Their data suggest that there could be a positive effect from the change (IE improved) but they did not look at what it would take to effectively change the coordination for long periods nor whether such changes actually provide any benefit to the rider, hence their statement that "Further studies are needed …"

In the case of Hug study I think it would be interesting to see if the variability they saw after one session tended to converge to an "average" pattern after a longer period training like that, how long it takes to "permanently" change the pattern, and whether, once the pattern is established, if there is an advantage. (It would also be interesting if they repeated this study in the aero position.) That is what needs to be done if one wants to study PowerCranks effectiveness. With the availability of cranks like the Pioneer system this ability will soon be available to almost anyone who wants to take this on at very little cost. Maybe we will see this in my lifetime.
 
Mar 10, 2009
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CoachFergie said:
Aerodynamics?

Anquetil had no problem with his frontal position, same position same technique except that mine is a more powerful version and more aerodynamic due to the use of the Scott Rake bars.
 

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